Moving Rate of Positive Patient Results as a Quality Control Tool for High-Sensitivity Cardiac Troponin T Assays

Background@#A small shift in high-sensitivity cardiac troponin T (hs-cTnT) assays can lead to different result interpretation and consequent patient management. We explored whether a small bias could be detected using conventional internal quality control (QC) procedures, evaluated the performance of moving average (MA)-based QC procedures, and proposed a new QC procedure based on the moving rate (MR) of positive patient results of hs-cTnT assays. @*Methods@#The ability of conventional QC to detect a 5 ng/L bias was examined using the 1 3s/ 22s/R4s multi-rule procedure as deviation rules.We developed MA and MR procedures for the hs-cTnT assay using eight months of patient data. The performance of different MA or MR procedures was investigated by calculating the median number of patient samples affected until a bias introduced into the dataset was detected (MNPed). After comparing the MNPed across different procedures, we selected an optimal MA or MR procedure for validation. Validation graphs were plotted using the minimum, median, and maximum number of results affected until bias detection. @*Results@#Our conventional QC procedures could not detect a positive bias of 5 ng/L. When a positive bias was introduced, MNPed was much higher using MA than using MR, with cut-off values of 5 ng/L and 14 ng/L, respectively. MR validation charts for optimal procedures provided insight into the MR performance. @*Conclusions@#The MR procedure could detect different errors with few false alarms. In the hs-cTnT assay, the MR procedure with a smaller cut-off value outperformed MA and conventional QC procedures for small bias detection.

Detection and preanalytical quality control of circulating microRNA / 中华检验医学杂志

Circulating microRNAs (miRNAs) have been confirmed to play an important role in biological processes,such as cell proliferation,differentiation and apoptosis.Founded on the high stability and minimal invasiveness,circulating miRNAs could be applied to the clinical practice as biomarkers.There are many technological approaches and platforms for circulating miRNAs detection but without a consistent protocol.Meanwhile,there are various factors affecting circulating miRNAs detection.In this review,technical factors and preanalytical factors in the circulating miRNA profiling are explored.